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Two Surprising NewCharmed Strange Mesons
John Bartelt
SLAC & BABAR
September, 2003 — DESY
John Bartelt, SLAC September, 2003 — DESY
Two Surprising New Charmed Strange Mesons
I am reporting on work by Antimo Palano & other BaBarians.
Plus comparisons to other experiments’ results.
Outline
• Historical and Theoretical Background
• BABAR’s discovery of the D∗sJ(2317)+
• The Second State
• Conclusions
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John Bartelt, SLAC September, 2003 — DESY
Charmed Mesons: Some History
• 1974: Charm (J/ψ) discovered
• 1976: Open Charm observed: D+, D0
• 1976: De Rujula, Georgi, Glashow: light-degrees decouple
• 1989: “Heavy Quark Symmetry”
Systems with One Heavy Quark:
• Light Degrees of Freedom Decouple from Heavy
• j` = L⊗ s` is conserved in limit mh→∞
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John Bartelt, SLAC September, 2003 — DESY
Charmed Mesons: Lab for Heavy Quark Studies
Mass of the Charm Quark ∼ 1500 MeV/c2 � ΛQCD
Should make it a good testing ground for HQS, “Heavy Quark
Effective Theory”, etc.
What is learned in Charm can be applied to the Bottom system
First, some background on Charm Spectroscopy
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John Bartelt, SLAC September, 2003 — DESY
Heavy-Light Spectroscopy
It’s like the hydrogen atom.
For mh→∞, sh = jh is fixed.
So j` = s` ⊗ L is separately conserved.
For L = 1 states this means:
⇒ j` = 3/2 states decay via D-wave
⇒ j` = 1/2 states decay via S-wave.
=⇒ j` = 3/2 states should be narrow
=⇒ j` = 1/2 states should be broad.
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John Bartelt, SLAC September, 2003 — DESY
HQ Potential Model Schematic
L = 1j` = 3/2
j` = 1/2
L = 0j` = 1/2
Spin-Orbit Tensor
D∗s2(2573)
+
Ds1(2536)+
D∗s(2112)
+
Ds(1968)+
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John Bartelt, SLAC September, 2003 — DESY
Heavy-Light Spectrscopy (2)
L = 0: one doublet:
1/2S0: Ds(1968)+ (0−)1/2S1: D
∗s(2112)
+ (1−)
L = 1: two doublets
1/2P0: D∗s0(?)
+ (0+)1/2P1: Ds1(?)+ (1+) e
—could be mixed3/2P1: Ds1(2536)+ (1+) c3/2P2: D
∗sJ(2573)+ (2+) [J=2 favored, not established]
Di Pierro & Eichten’s notation:j`LJ
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John Bartelt, SLAC September, 2003 — DESY
Heavy-Light Spectroscopy (3)
By c.1994, the six j` = 3/2 narrow P -wave charmed mesons
had been found.
JP of the states are not rigorously established,
but not subject to serious doubt.
“Natural” (or “Normal”) Spin-Parity:
True if P = (−1)J [0+, 1−, 2+ . . .].
Flavored natural states get a ∗.
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John Bartelt, SLAC September, 2003 — DESY
Charmed Meson Spectroscopy c.1995
D(1867)
D∗(2008)
D1(2423)D∗
2(2459)
Ds(1968)+
D∗s(2112)
+
Ds1(2536)+
D∗s2(2573)
+
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
Kπ
γ
Observed States and Decays
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John Bartelt, SLAC September, 2003 — DESY
Predictions for L = 1 j` = 1/2 Charmed Mesons
Many potential model calculations for masses and widths.
I mention only two examples here:
Godfrey & Kokoski PRD 43, 1679 (1991)
Di Pierro & Eichten PRD 64, 114004 (2001)
L = 1 j` = 1/2 (MeV/c2)
1/2D01/2D1
1/2Ds01/2Ds1
m Γ m Γ m Γ m ΓG&K 2400 290 2470 250 2480 310 2560 140
DP&E 2377 110 2490 110 2487 140 2605 130
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John Bartelt, SLAC September, 2003 — DESY
Predictions for L = 1 j` = 1/2 Charmed Mesons
D(1867)
D∗(2008)
D1(2423)D∗
2(2459)
Ds(1968)+
D∗s(2112)
+
Ds1(2536)+
D∗s2(2573)
+
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
2500
2400
2300
DK thresh
D∗K thresh
Godfrey & Kokoski DiPierro & Eichten
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John Bartelt, SLAC September, 2003 — DESY
BABAR
BABAR: General purpose solenoidal spectrometer with silicon
vertex tracker, CsI calorimeter, DIRC particle ID, and
instrumented flux return for muon and KL detection.
Operates at PEP-II asymmetric B-Factory:
Ee−=9.0 GeV, Ee+=3.1 GeV√S = m(Υ(4S)) or just below
Best luminosity: 6.582× 1033 cm−2 sec−1
σ(e+e−→ cc) ≈ 1.3 nb
For 91 fb−1for this analysis; ∼120 million charm events
Or roughly 1.2 million D0→ K−π+
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John Bartelt, SLAC September, 2003 — DESY
PEP-II and BABAR
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John Bartelt, SLAC September, 2003 — DESY
United KingdomBrunel UniversityQueen Mary, U. LondonImperial College, LondonRoyal Holloway U. LondonRutherford Appleton Lab.U. BirminghamU. BristolU. EdinburghU. LiverpoolU. Manchester
RussiaBudker Institute, Novosibirsk
ItalyLab. Nazionali di Frascati dell’ INFNINFN and U. BariINFN and U. FerraraINFN and U. GenovaINFN and U. PerugiaINFN and U. MilanoINFN and U. NapoliINFN and U. PadovaINFN and U. PaviaINFN and U. PisaINFN and U. Roma La SapienzaINFN and U.TorinoINFN and U.Trieste
ChinaInst. of High Energy Physics, Beijing
CanadaMcGill U.U. British ColumbiaU.VictoriaU. Montreal
FranceLAPP,AnnecyEcole PolytechniqueLAL, OrsayDAPNIA, CEN-SaclayLPHNE and U. ParisVI–VII
GermanyRuhr U. BochumTech. U. DresdenU. RostockHeidelberg
NorwayU. Bergen
The NetherlandsNIKHEF,Amsterdam
USACaltechColorado StateFlorida A&MHarvardIowa State U.LBNLLLNLMITMount Holyoke CollegeOhio State U.PrairieView A&M U.Princeton U.SLACStanford U.SUNY AlbanyU.C. IrvineU.C. Los AngelesU.C. San DiegoU.C. Santa BarbaraU.C. Santa CruzU. CincinnatiU. ColoradoU. IowaU. LouisvilleU. MarylandU. MassachusettsU. MississippiU. Notre DameU. OregonU. PennsylvaniaU. South CarolinaU.TennesseeU.Texas AustinU.Texas DallasU.Wisconsin (3&4)Vanderbilt U.Yale U.
The BaBarCollaboration
10 countries77 Institutions~580 Physicists
50% Outside U.S.A.
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John Bartelt, SLAC September, 2003 — DESY
An Unexpected Signal
Early 2003: Antimo Palano was studying D+s π
0.
To everyone’s surprise, he found a new, huge signal.
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John Bartelt, SLAC September, 2003 — DESY
Analysis Details
See also PRL, 90, 242001 (2003)
Used 91 fb−1 collected on Υ(4S) and just below.
Studying e+e− → cc, not B decay (so far).
Reconstruct D+s → K+K−π+.
• Kaons selected by Cerenkov (DIRC) & dE/dx
• Pion: any charged track that fails Kaon criteria
• K+K−π+ fit to common vertex, P > 0.1%.
• φπ+: ±10 MeV/c2 around m(φ); | cos θv| > 0.5
• K∗0K+: ±50 MeV/c2 around m(K∗0); | cos θv| > 0.5
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John Bartelt, SLAC September, 2003 — DESY
An Event
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John Bartelt, SLAC September, 2003 — DESY
Analysis Details (2)
Reconstruct π0→ γγ
• E(γ) > 100 MeV
• One-constraint fit to π0 mass (P > 1%)
• Only use π0 if no other π0 candidate uses either γ
• p∗(K+K−π+π0) > 2.5 GeV/c.
π0 signal region: 122 MeV/c2< m(γγ) <148 MeV/c2
sidebands: 90—110 MeV and 160—180 MeV
D+s signal region: 1955 MeV/c2< m(K+K−π+) <1979 MeV/c2
sidebands: 1912—1934 MeV/c2 and 1998—2020 MeV/c2
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John Bartelt, SLAC September, 2003 — DESY
Combining D+s and π0 Candidates
X XXXXXXXXXXXX
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John Bartelt, SLAC September, 2003 — DESY
Really π0?
Note: these γγ pairs do not have same cuts as π0 candidates.
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John Bartelt, SLAC September, 2003 — DESY
Some More Checks
• Signal only appears in D+s π
0, not sidebands
• Signal in D+s → φπ+ and D+
s → K∗0K+ as expected
• Try vetoing D+s from D∗
s(2112)+ → D+
s γ
• Nothing similar in D+π0
• Check for particle mis-ID (K/π)
• Nothing in Monte Carlo that makes a peak here
• p∗ spectrum looks OK
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John Bartelt, SLAC September, 2003 — DESY
φπ+ vs. K∗0K+
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John Bartelt, SLAC September, 2003 — DESY
Fit the Combined Data
p∗ > 3.5 GeV/c
1267± 53 events
M = 2316.8±0.4 MeV/c2
σ = 8.6± 0.4 MeV/c2
[Detector Resolution]
Statistical errors only!
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John Bartelt, SLAC September, 2003 — DESY
Cross Check: use D+s → K+K−π+π0
p∗ > 3.5 GeV/c
273± 33 events
M = 2317.6±1.3 MeV/c2
σ = 8.8± 1.1 MeV/c2
[Detector Resolution]
Statistical errors only!
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John Bartelt, SLAC September, 2003 — DESY
Initial Conclusions• Signal width consistent with detector resolution, as estimated
by Monte Carlo. ⇒ Γ <∼ 10 MeV/c2
• Decay to 2 pseudoscalars implies natural spin-parity
• If it is a cs state, decay violates isospin conserveration.
• If it is the missing 0+, it is ∼170 MeV/c2 lighter than
expected
• Below D0K+ decay threshold forces this decay mode
• Isospin violating decay implies very narrow.
Call it D∗sJ(2317)+. What else can we learn about it?
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John Bartelt, SLAC September, 2003 — DESY
Decay Angleuncorrected efficiency corrected
Consistent with
J = 0 particle, or
unaligned J > 0 state.
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John Bartelt, SLAC September, 2003 — DESY
Other Decay Modes?Nothing seen at
2317 MeV/c2 in
D+s γ
D+s γγ
D∗+s γ
D+s π
0γ
D∗+s π0
BABAR PRL 90, 242001
(2003)
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John Bartelt, SLAC September, 2003 — DESY
What is that at ∼2460 MeV/c2?
Could X(2460)→ D+s π
0γ be the real source of the
peak at 2317 MeV/c2, if we have missed the γ?
No!• Relative rate is too small.
• Would not produce a gaussian signal shape
• Mass is not quite right.
But, if real, can produce some background under the peak at
2317 MeV/c2. [More on this later.]
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John Bartelt, SLAC September, 2003 — DESY
Why the peak near 2460 MeV/c2 is Tricky
D∗s(2112)
+ + π0random crosses D∗
sJ(2317)+ + γrandom
at m(D+s π
0γ) ≈ 2460 MeV/c2.
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John Bartelt, SLAC September, 2003 — DESY
BABAR PRL 90, 242001 (2003)
“Although we rule out the decay of a state of mass 2.46 GeV/c2
as the sole source of the D+s π
0 mass peak corresponding to
the D∗sJ(2317)+, such a state may be produced in addition to
the D∗sJ(2317)+. However, the complexity of the overlapping
kinematics of the D∗s(2112)
+ → D+s γ and D∗
sJ(2317)+ →D+
s π0 decays requires more detailed study, currently underway,
in order to arrive at a definitive conclusion.”
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John Bartelt, SLAC September, 2003 — DESY
Other Experiments Confirm D∗sJ(2317)+
2.10 2.20 2.30 2.40 2.50 2.60M(Dsπ
0) (GeV/c2)
0
40
80
Eve
nts/
5MeV
/c2
Data
qq Monte Carlo
GeV/c2
Ds(
2317
)/5M
eV
0
50
100
150
200
250
300
0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 0.55 0.6
CLEO 13.5 fb−1 Belle preliminary 78 fb−1
CDF (preliminary): no signal for D∗sJ(2317)+ → D+
s π+π−
[0+→ 0−0−0− is forbidden]
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John Bartelt, SLAC September, 2003 — DESY
The DsJ(2463)+
CLEO’s paper (submitted to PRD) is entitled:
Observation of a Narrow Resonance of Mass 2.46 GeV/c2
Decaying to D∗+s π0 and Confirmation of the D∗
sJ(2317)+
State
Belle has also seen two states.
What does BABAR now have to say about the second peak?
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John Bartelt, SLAC September, 2003 — DESY
The Mass Peak
Inclusive D+s π
0γ events
D+s side band events
Preliminary
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John Bartelt, SLAC September, 2003 — DESY
A 3-D View
A prominent peak appears in data, not in Monte Carlo, which
includes the D∗sJ(2317)+.
Preliminary
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John Bartelt, SLAC September, 2003 — DESY
D+s γπ
0: Sideband Subtraction
Change variables: D∗sJ(2317)++
⇓random γ
∆m(D+s γ) ≡
m(D+s γ)−m(D+
s )
D∗+s + random π0=⇒
Preliminary
∆m(D∗+s π0) ≡ m(D+
s γπ0)−m(D+
s γ)
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John Bartelt, SLAC September, 2003 — DESY
D+s γπ
0: Sideband Subtraction (2)Signal & Sideband Difference, with Fit
peak: ∆m(D∗+s π0) = 346.2± 0.9 MeV/c2statistical error only
↙D∗
sJ(2317)+ +γ
©
Preliminary
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John Bartelt, SLAC September, 2003 — DESY
Channel Likelihood Method
Assign likelihoods to each event for:
1. DsJ(2458)+ → D∗sJ(2317)+γ
2. DsJ(2458)+ → D∗s(2112)
+π0
3. background D∗sJ(2317)+ plus random γ
4. background D∗s(2112)
+ plus random π0
5. combinatorial background
Assume the three-body decayDsJ(2458)+ → D+s π
0γ is absent.
Ignore any possible interference term (resolution would smear).
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John Bartelt, SLAC September, 2003 — DESY
Channel Likelihood Fit Results
D+s γπ
0
weightedD∗+
s π0
weightedD∗
sJ(2317)+γ
D+s π
0
projection
D+s γ
projection
↖←Note: different scales!
Preliminary
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John Bartelt, SLAC September, 2003 — DESY
Preliminary Results
• 174± 22 events, DsJ(2458)+ → D∗s(2112)
+π0
• 0± 19 events, DsJ(2458)+ → D∗sJ(2317)+γ
• m(DsJ(2458)+) = 2458.0± 1.0± 1.0 MeV/c2
• Gaussian σ = 8.5± 1.0 MeV/c2: Detector Resolution
B(DsJ(2458)+ → D∗sJ(2317)+γ)
B(DsJ(2458)+ → D∗s(2112)+π0)
< 0.2 (95%C.L.)
Refit D∗sJ(2317)+ → D+
s π0 (account for DsJ(2458)+bkgd):
m(D∗sJ(2317)+) = 2317.3± 0.4± 0.8 MeV/c2
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John Bartelt, SLAC September, 2003 — DESY
Decay Mode
Solid Hists: DsJ(2458)+ → D∗s(2112)
+π0 Monte Carlo
Dashed Hists: DsJ(2458)+ → D∗sJ(2317)+γ Monte Carlo
Data agree with Solid histograms. Preliminary
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John Bartelt, SLAC September, 2003 — DESY
Spin-Parity of DsJ(2458)+?
• Decay to D∗+s π0 (1−0−) rules out 0+
• Decay mode also makes other natural JP (1−, 2+, . . .) highly
unlikely (decay to D0K+, D+K0 available)
• That leaves unnatural: 0−, 1+, 2−
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John Bartelt, SLAC September, 2003 — DESY
Helicity Angle
ϑh: angle between γ and D∗s(2112)
+ in D∗s(2112)
+ rest frame.
JP = 0− ⇒ sin2 ϑh
solid histogram
disfavored
JP = 1−, 2+ . . .
⇒ 1 + cos2 ϑh
dashed histogram
OK (but unlikely)
Preliminary
JP = 1+, 2−, . . .: depends on alignment: no conclusion.
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John Bartelt, SLAC September, 2003 — DESY
Relative Production Rate
Preliminary
P ≡ σ(DsJ(2458)+)B(DsJ(2458)+ → D∗s(2112)
+π0)σ(D∗
sJ(2317)+)B(D∗sJ(2317)+ → D+
s π0)
= 0.23± 0.03 (stat.)± 0.03 (syst.)
for p∗ > 3.5 GeV/c for both states
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John Bartelt, SLAC September, 2003 — DESY
Comparisons with CLEO and Belle
D∗sJ(2317)+mass:
BABAR 2317.3± 0.4± 0.8 MeV/c2 [preliminary]Belle 2317.2± 0.5± 0.9 MeV/c2 continuum [prelim.]
Belle 2319.8± 2.1± 2.0 MeV/c2 B decay
CLEO 2318.5± 1.2± 1.2 MeV/c2
my average: 2317.4± 0.5± 0.6 MeV/c2 [χ2 = 1.2]first error: stat&syst; second error from D+
s mass (common)
• Width is less than resolution. (Γ < 7 MeV/c2: CLEO)
• No other decay modes seen.
• Everything consistent with JP = 0+.44
John Bartelt, SLAC September, 2003 — DESY
Comparisons with CLEO and Belle (2)
DsJ(2458)+mass (from D∗s(2112)
+π0)
BABAR 2458.0± 1.0± 1.0 MeV/c2 [Preliminary]Belle 2456.5± 1.3± 1.1 MeV/c2 continuum [prelim.]
Belle 2459.2± 1.6± 2.0 MeV/c2 B decay
CLEO 2463.1± 1.7± 1.2 MeV/c2
my average: 2458.6± 0.8± 0.7 MeV/c2 [χ2 = 6.4]
first error: stat&syst; second error from D∗+s mass (common)
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John Bartelt, SLAC September, 2003 — DESY
Comparisons with CLEO and Belle (3)
P, the DsJ(2458)+/D∗sJ(2317)+ production ratio
BABAR 0.23± 0.03± 0.03 p∗ > 3.5 GeV/c [prelim.]Belle 0.26± 0.05± 0.06 p∗ > 3.5 GeV/c [prelim]
CLEO 0.44± 0.13± 0.03(?) p∗ > 3.5 GeV/cBABAR agrees with Belle, not so well with CLEO
Belle also sees the decay DsJ(2458)+ → Ds(1968)+γ in bothB decays and continuum events.
B(DsJ(2458)+→ D+s γ)
B(DsJ(2458)+ → D∗s(2112)+π0)
= 0.38± 0.11± 0.04{B}
= 0.63± 0.15± 0.15{cc}[prelim]
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John Bartelt, SLAC September, 2003 — DESY
Belle: Exclusive B Decay
0
10
20 (a)
0
10
(b)
0
10
20
-0.2 -0.1 0 0.1 0.2
(c)
∆E (GeV)
Eve
nts
/(0
.01
Ge
V) 0
10
20 (a)
0
10
20 (b)
0
20
2.2 2.3 2.4 2.5 2.6
(c)
M(DsJ ) (GeV/c 2)E
ven
ts/(
0.0
1 G
eV
)
(a) D∗sJ(2317)+ → D+
s π0
B → DDsJ (b) DsJ(2458)+ → D∗+s π0
(c) DsJ(2458)+ → D+s γ
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John Bartelt, SLAC September, 2003 — DESY
Belle: Helicity Angle
0
2
4
6
8
10
12
-1 -0.5 0 0.5 1
cos( θDsγ)
Eve
nts/
(0.
25)
B → DDsJ(2458)+,
DsJ(2458)+ → D+s γ
Solid line: J = 1Dotted line: J = 2
J = 1 clearly favored
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John Bartelt, SLAC September, 2003 — DESY
Charm Spectroscopy Now
D(1867)
D∗(2008)
D1(2423)D∗
2(2459)
Ds(1968)+
D∗s(2112)
+
Ds1(2536)+
D∗s2(2573)
+
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
CLEO 1999
BELLE 2002
2500
2400
2300
DK thresh
D∗K thresh
D∗sJ(2317)
+
DsJ(2458)+
in B decay
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John Bartelt, SLAC September, 2003 — DESY
Observations of Non-Strange j` = 1/2 States
To see broad j` = 1/2 states, need to look in B decay.
CLEO CONF 99-6 (1999):
observe B− → D01π
−, D01 → D∗+π−:
m = 2461+41−34 ± 10 ± 32 MeV/c2 and Γ = 290+101
−79 ± 26 ±36 MeV/c2
BELLE CONF-0235 (2002):
observe B− → D01π
−, D01 → D∗+π−:
m = 2400±30±20 MeV/c2 and Γ = 380±100±100 MeV/c2
and observe B−→ D∗00 π
−, D∗00 → D+π−:
m = 2290± 22± 20 MeV/c2 and Γ = 305± 30± 25 MeV/c2
50
John Bartelt, SLAC September, 2003 — DESY
Potential Models Need Revision
L = 1
j` = 3/2
j` = 1/2
Spin-Orbit Tensor
D∗s2(2573)
+
Ds1(2536)+
DsJ(2458)+
D∗sJ(2317)+
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John Bartelt, SLAC September, 2003 — DESY
Theoretical Discussion
• Cho & Wise (1994) Predicted rate for isopsin-violating decay
D∗s(2112)
+ → D+s π
0. Described as occuring through η/π0
mixing
• Cho & Trivedi (1994) predicted rate for D+s1 →
D∗s(2112)
+π0, if its mass were as low as 2480 MeV/c2.(Dismiss the possibility of D∗+
s0 being below DK threshold.)
Γ(DsJ(2458)+ → D∗+s π0) ≈ 20 keV/c2
• Cahn & Jackson can get potential model to give right masses:
but the mixing comes out wrong
• If Belle/CLEO results for non-strange states are right,
m(cs)−m(cd) ∼ 50 MeV/c2, not ∼100 MeV/c2
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John Bartelt, SLAC September, 2003 — DESY
Theoretical Discussion (2)
• Chiral models seem to do fairly well at predicting masses:
m(D∗+s )−m(D+
s ) = m(DsJ(2458)+)−m(D∗sJ(2317)+)
• Bardeen, Eichten & Hill (2003) also predicts rates
• Many other ideas floated when D∗sJ(2317)+ first reported
• Four-quark state?
• Di-meson moelcule? (Lipkin & Isgur, 1981)
• However, all data is consistent with the two states being cs
mesons, with J = 0, 1 (in my opinion)
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John Bartelt, SLAC September, 2003 — DESY
Summary and Conclusions
• BABAR discovered the surprising D∗sJ(2317)+
• BABAR has also observed the DsJ(2458)+
• CLEO and Belle have also provided import observations
which help define the identity of these states
• BABAR is continuing its studies of these new states, in both
cc events and in B decays, and hopes to publish more results
soon.
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John Bartelt, SLAC September, 2003 — DESY
Extra Foils
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John Bartelt, SLAC September, 2003 — DESY
Compare: Charmonium Spectroscopy
S = s1 ⊗ s2 = 0, 1J = S ⊗ LP = −1
L+1
notation:2S+1
LJ
Appropriate for two equal mass constituents.
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John Bartelt, SLAC September, 2003 — DESY
Charmonium Spectroscopy (cont.)
L = 0: two singlets1S0: ηc (0−)3S1: J/ψ (1−)
L = 1: singlet and triplet1P1: hc (1+) (C = −)3P0: χc0 (0+)3P1: χc1 (1+) (C = +)3P2: χc2 (2+)
The two 1+ states cannot mix.
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John Bartelt, SLAC September, 2003 — DESY
Charmed Meson Spectroscopy (2)
D(1867)
D∗(2008)
D1(2423)D∗
2(2459)
Ds(1968)+
D∗s(2112)
+
Ds1(2536)+
D∗s2(2573)
+
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
0− 1− 0+ 1+ 1+ 2+
j =1/2 j =1/2 j =3/2L = 0 L = 1
ππ ηK
Observed States: Hypothetical Decays
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John Bartelt, SLAC September, 2003 — DESY
Helicity Angle Cut for φ or K∗0
59
John Bartelt, SLAC September, 2003 — DESY
p∗ Spectrum for D∗sJ(2317)+
60
John Bartelt, SLAC September, 2003 — DESY
2460 with missed γ
61
John Bartelt, SLAC September, 2003 — DESY
D∗s(2112)+→ D+s γ Background?
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John Bartelt, SLAC September, 2003 — DESY
Search for D∗sJ(2317)+→ D+s π
0π0
63